1. Field of the Invention
The present invention relates to a cap, and particularly to a vacuum pick up cap for using in socket to facilitate operation.
2. Description of Related Art
Generally, a chip module socket, such as CPU socket, has a small fixing base surface because of multiples of through-holes. In order to position the CPU socket on a printed circuit board (hereinafter PCB), one skilled in the art need put a pick up cap (see FIG. 6) on the CPU socket. Consequently, the pick up cap is sucked and carried by a vacuum device, thereby carrying the CPU socket. Finally, the CPU socket can be accurately located on the PCB. The pick up cap 2 has an upper surface 4, a bottom surface 6, and a series of protrusions 8 projecting from the bottom surface. The protrusions can interference fit in a corresponding aperture defined in the CPU socket.
However, because of inherent tolerance of the aperture of the CPU socket and the protrusions, there may happen that the protrusions cannot be inserted through the aperture. On the other hand,excessive interference between the aperture and the protrusions may result in damage of the aperture.
Accordingly, the object of the present invention is to provide a vacuum pick up cap which can be easily and reliably assembled to a CPU socket.
In order to achieve the object set forth, a vacuum pick up cap for use in transporting by vacuum suction a socket is provided. The socket includes a base having an opening, and a cover having a through-hole and slidablystacked on an upper surface of the base to moveable between an open position and a closed position. The pick up cap has a flat surface and a leg. In the open position, the leg extends through the through-hole and into the opening. In the closed position, the leg is retained in the opening by a periphery of the through-hole. Thus, such a pick up cap may be freely, i.e., zero insertion force (ZIF), initially mounted to the socket and successively locked thereto. The withdrawal of the pick up cap from the socket also achieves the zero force thereof.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.